Investigation of Contacts of Persons with Infectious Tuberculosis, 2005

Division of Tuberculosis Elimination

Centers for Disease Control and Prevention

National Tuberculosis Controllers Association

Centers for Disease Control and Prevention

Background (1)
        - 1962: Isoniazid (INH) demonstrated to be effective in preventing tuberculosis (TB) among household contacts of persons with TB disease

Investigation and treatment of contacts with latent TB infection (LTBI) quickly becomes strategy in TB control and elimination in the U.S.
        - 1976: American Thoracic Society (ATS) published guidelines for investigation, diagnostic evaluation, and medical treatment of TB contacts

Background (2)
        - 2005: National TB Controllers Association (NTCA) and CDC release guidelines on the investigation of contacts of persons with infectious TB

Expanded guidelines on investigation of TB exposure and transmission, and prevention of future TB cases through contact investigations

Standard framework for assembling information and using findings to inform decisions

Contact Investigations – A Crucial Prevention Strategy
        - On average, 10 contacts are identified for each person with infectious TB in the U.S.
        - 20%–30% of all contacts have LTBI
        - 1% of contacts have TB disease
        - Of contacts who will ultimately have TB disease, approximately one-half develop disease in the first year after exposure

Benefits of Contact Investigations
        - Finding and treating additional TB disease cases (potentially interrupting further transmission)
        - Finding and treating persons with LTBI to avert future cases

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Contact Investigation Responsibilities
        - Health departments are responsible for ensuring the conduct contact investigations
        - Contact investigations are complicated activities that require 

Many interdependent decisions

Time-consuming interventions

Key Terms (1)
        - Case – A particular instance of a disease (e.g., TB). A case is detected, documented, and reported.
        - Contact – Someone who has been exposed to M. tuberculosis by sharing air space with a person with infectious TB.

Key Terms (2)
        - Index – The first case or patient who comes to attention as indicator of a potential public health problem.
        - Source case or patient – The case or person who was the original source of infection for secondary cases or contacts; can be, but is not necessarily, the index case.

Decisions to Initiate a Contact Investigation

Decisions to Initiate a Contact Investigation
        - Public health officials must decide which

Contact investigations should be assigned a higher priority

Contacts to evaluate first
        - Decision to investigate an index patient depends on presence of factors used to predict likelihood of transmission

Factors that Predict Likely Transmission of TB
        - Anatomical site of the disease
        - Positive sputum bacteriology
        - Radiographic findings
        - Behaviors that increase aerosolization of respiratory secretions
        - Age
        - HIV status
        - Administration of effective treatment

Characteristics of the Index Patient Associated with Increased Risk of TB Transmission
        - Pulmonary, laryngeal, or pleural TB
        - Acid-fast bacilli (AFB) positive sputum smear
        - Cavitation on chest radiograph
        - Adolescent or adult patient
        - No or ineffective treatment of TB disease

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Behaviors of the Index Patient Associated with Increased Risk of TB Transmission
        - Frequent coughing
        - Sneezing
        - Singing
        - Close social network

Initiating a Contact Investigation (1) 
        - Consider if index patient has 

Confirmed or suspected pulmonary, laryngeal, or pleural TB

Chest radiograph consistent with pulmonary TB
        - Recommended if

Sputum smear has AFB on microscopy

Chest radiograph indicates presence of cavities in the lung (AFB sputum smear negative)

Initiating a Contact Investigation (2)
        - Not generally indicated if

 Sputum smear has AFB on microscopy and nucleic acid amplification (NAA) tests for M.tuberculosis are negative

 Initiating a Contact Investigation (3) 
        - Persons with AFB smear or culture-positive sputum and cavitary TB assigned the highest priority
        - Should not be initiated for contacts who have suspected TB disease and minimal findings in support of pulmonary TB diagnosis

Initiating a Contact Investigation (3) 
        - Initiation of other investigations  depends on

Availability of resources to be allocated

Achievement of objectives for higher priority contact investigations 

Decision to Initiate a TB Contact Investigation

*Acid-fast bacilli

†Nucleic acid assay

§Approved indication for NAA

¶Chest radiograph

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Investigating the Index Patient and Sites of Transmission

Comprehensive Index Patient Information 
        - Foundation of a contact investigation
        - Information to be gathered includes

Disease characteristics

Onset time of illness

Names of contacts

Exposure locations

Current medical factors (e.g., initiation of treatment and drug susceptibility results) 

Preinterview Phase
        - Collect patient background information and circumstances of illness

Possible sources include

Medical record

Reporting physician
        - Match patient’s name to prior TB registries and the surveillance database 

Data to Collect in Preinterview Phase (1)
        - History of previous TB exposure or infection
        - History of previous TB disease and treatment
        - Anatomical sites of TB disease
        - Symptoms of illness
        - Date of onset
        - Chest radiography results
        - Other diagnostic imaging study results

Data to Collect in Preinterview Phase (2)
        - Histologic or bacteriologic analysis results
        - Current bacteriologic results
        - Anti-TB chemotherapy regimen
        - HIV testing results
        - Patient’s concurrent medical conditions
        - Other diagnoses that may influence or impinge on the interview
        - Identifying demographic information 

Determining the Infectious Period
        - Focuses investigation on contacts most likely to be at risk for infection
        - Sets time frame for testing contacts 
        - Information to assist with determining infectious period

Approximate dates TB symptoms were noticed

Bacteriologic results

Extent of disease 

Start of Infectious Period
        - Cannot be determined with precision; estimation is necessary
        - Start is 3 months before TB diagnosis (recommended)
        - Earlier start should be used in certain circumstances (e.g., patient aware of illness for longer period of time) 

Estimating the Beginning of the Infectious Period

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| Characteristic of Index Case                                                                                                                                                                                                  |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| TB symptoms                                                                                                                                                                                                                   | AFB sputum smear positive | Cavitary chest radiograph | Likely period of infectiousness |
| Yes                                                                                                                                                                                                                           | No | No | 3 months before symptom onset or 1st positive finding consistent with TB disease, whichever is longer |
| Yes                                                                                                                                                                                                                           | Yes | Yes | 3 months before symptom onset or 1st positive finding consistent with TB disease, whichever is longer |
| No                                                                                                                                                                                                                            | No | No | 4 weeks before date of suspected diagnosis |
| No                                                                                                                                                                                                                            | Yes | Yes | 3 months before positive finding consistent with TB |
| SOURCE: California Department of Health Services Tuberculosis Control Branch; California Tuberculosis Controllers Association. Contact Investigation Guidelines. Berkley, CA: California Department of Health Services; 1998. |

Closing the Infectious Period
        - Effective treatment for ≥2 weeks,
        - Diminished symptoms, and
        - Bacteriologic response 

Infectious period closed when all the following criteria are met

Exposure Period for Contacts

Determined by how much time the contact spent with the index patient during the infectious period

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Contact Investigation Interviews
        - Establishing trust and rapport with patient is critical
        - Interviewers should be trained in interview methods and tutored on the job
        - Conducted in patient’s primary language or in conjunction with a trained interpreter
        - Interviews should be conducted in person in the hospital, TB clinic, patient’s home, or a convenient location that accommodates the patients privacy 

Interviewing the Index Patient
        - Minimum of two interviews should be conducted

First interview should be conducted 

≤1business day of reporting for infectious patients

≤3 business days for others

Second interview conducted 1–2 weeks later
        - Additional interviews depend on the amount of information needed and time to develop rapport with patient 

Contact Investigation Interview General Principles
        - Establish rapport with patient
        - Exchange information 
        - Review transmission settings
        - Record sites of transmission
        - Compile list of contacts
        - Provide closure
        - Conduct follow-up interviews, if needed 

Proxy Interviews
        - Can build on the information provided by index patient
        - Essential when patient cannot be interviewed
        - Conducted with key informants most likely to know the patients’ practices, habits, and behaviors
        - Jeopardizes patient confidentiality 

Field Investigation (Site Visits)
        - Site visits are complementary to interviewing
        - Should be made ≤3 days of the initial interview
        - Elicits additional contact information; especially helpful for finding children 
        - Lack of site visits has contributed to TB outbreaks 

Follow-up Steps
        - Continuing investigation is shaped by reassessments of ongoing results
        - Notification and follow-up communication with other jurisdictions should be arranged for out-of-area contacts

Specific Investigation Plan
        - Investigation plan should include

Information gathered in interviews and site visits

Registry of contacts and their assigned priorities

Written timeline for monitoring the investigation progress

Data recorded on standardized forms
        - Part of the permanent medical record

Time Frames for Initial Follow-up of Contacts Exposed to TB

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| Type of Contact                                                                                                                                                                                                                                                                                                                                                      | Business days from listing of a contact to initial encounter* | Business days from initial encounter to completion of medical evaluation†   |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------------------------------------------------------|-----------------------------------------------------------------------------|
| High priority contact: index case AFB sputum smear positive or cavitary disease on chest x-ray                                                                                                                                                                                                                                                                       | 7                                                             | 5                                                                           |
| High priority contact: index case AFB sputum smear negative§                                                                                                                                                                                                                                                                                                         | 7                                                             | 10                                                                          |
| Medium priority contact: regardless of AFB sputum smear or culture result                                                                                                                                                                                                                                                                                            | 14                                                            | 10                                                                          |
| *A face-to-face meeting that allows the health care worker to assess the overall health of the contact, administer a TST, and schedule further evaluation.†The medical evaluation is complete when the contact’s status (LTBI or TB disease) is determined.§Abnormal chest x-ray consistent with TB disease, might be NAA positive and /or AFB culture positive      |
| SOURCE: California Department of Health Services Tuberculosis Control Branch; California Tuberculosis Controllers Association. Contact Investigation Guidelines. Berkley, CA: California Department of Health Services; 1998.                                                                                                                                        |

Assigning Priorities to Contacts

Assigning Priorities to Contacts (1)
        - Priorities should be assigned to contacts and resources allocated to complete all investigative steps for high-and medium-priority contacts.
        - Any contact not classified as high or medium priority is assigned a low priority. 

Assigning Priorities to Contacts (2)
        - Priorities based on likelihood of infection and hazards to the contact if infected
        - Priority scheme directs resources to contacts who 

Have secondary case of TB disease

Have recent M. tuberculosis infection (most likely to benefit from treatment)

Are most likely to develop TB disease if infected or could suffer severe morbidity if they develop TB disease 

Factors for Assigning Contact Priorities
        - Characteristics of the index patient
        - Characteristics of contacts
        - Age
        - Immune status
        - Other medical conditions
        - Exposure

Prioritization of Contacts (1)

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| Patient has pulmonary, laryngeal, or pleural TB with cavitary lesion on chest radiograph or is AFB sputum smear positive             |
|--------------------------------------------------------------------------------------------------------------------------------------|
| Household contact                                                                                                                    | High |
| Contact <5 years of age                                                                                                           | High |
| Contact with medical risk factor (HIV or other medical risk factor)                                                                  | High |
| Contact with exposure during medical procedure (bronchoscopy, sputum induction, or autopsy)                                          | High |
| Contact in a congregate setting                                                                                                      | High |
| Contact exceeds duration/environment limits (limits per unit time established by the health department for high-priority contacts)   | High |
| Contact is ≥ 5 years and ≤ 15 years of age                                                                                           | Medium |
| Contact exceeds duration/environment limits (limits per unit time established by the health department for medium-priority contacts) | Medium |
| Any contact not classified as high or medium priority is assigned a low priority.                                                    |

Prioritization of Contacts (2)

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| Patient is a suspect or has confirmed pulmonary/pleural TB – AFB smear negative, abnormal chest radiograph consistent with TB disease, may be NAA and/or culture positive   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Contact <5 years of age                                                                                                                                                  | High |
| Contact with medical risk factor (e.g., HIV)                                                                                                                                | High |
| Contact with exposure during medical procedure (bronchoscopy, sputum induction, or autopsy)                                                                                 | High |
| Household contact                                                                                                                                                           | Medium |
| Contact exposed in congregate setting                                                                                                                                       | Medium |
| Contact exceeds duration/environment limits (limits per unit time established by the local TB control program)                                                              | Medium |
| Any contact not classified as high or medium priority is assigned a low priority.                                                                                           |

Prioritization of Contacts (3)

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| Patient is a suspect pulmonary TB case – AFB smear negative, NAA negative/culture negative, abnormal chest radiograph not consistent with TB disease   |
|--------------------------------------------------------------------------------------------------------------------------------------------------------|
| Household contact                                                                                                                                      | Medium |
| Contact <5 years of age                                                                                                                             | Medium |
| Contact with medical risk factor (e.g., HIV infection or other immunocompromising condition)                                                           | Medium |
| Contact with exposure during medical procedure (bronchoscopy, sputum induction, or autopsy)                                                            | Medium |
| Any contact not classified as high or medium priority is assigned a low priority.                                                                      |

Diagnostic and Public Health Evaluation of Contacts

Initial Assessment of Contacts
        - Should be accomplished within 3 working days of the contact having been listed in the investigation
        - Gathers background health information
        - Permits face-to-face assessment of person’s health

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Information to Collect During Initial Assessment (1)
        - Previous M. tuberculosis infection or disease and related treatment
        - Contact’s verbal report and documentation of previous TST results
        - Current symptoms of TB illness

Information to Collect During Initial Assessment (2)
        - Medical conditions making TB disease more likely
        - Mental health disorders
        - Type, duration, and intensity of TB exposure
        - Sociodemographic factors 

Information to Collect During Initial Assessment (3)
        - HIV status; contacts should be offered HIV counseling and testing if status unknown
        - Information regarding social, emotional, and practical matters that might hinder participation

Reassess Strategy After Initial Information Collected

After initial information collected

Priority assignments should be reassessed

Medical plan for diagnostic tests and possible treatment can be formulated for high- and medium-priority contacts

Tuberculin Skin Testing
        - All high or medium priority contacts who do not have a documented previous positive tuberculin skin test (TST) or previous TB disease should receive a TST at the initial encounter.
        - If not possible, TST should be administered

≤7 working days of listing high-priority contacts

≤14 days of listing medium-priority contacts

Interpreting Skin Test Reaction
        - ≥5 mm induration is positive for any contact
        - Two-step procedure should not be used for testing contacts
        - A contact whose second TST is positive after initial negative result should be classified as recently infected

Postexposure Tuberculin Skin Testing
        - Window period is 8–10 weeks after exposure ends
        - Contacts who have a positive result after a previous negative result are said to have had a change in tuberculin status from negative to positive

Medical Evaluation

All contacts whose skin test reaction induration is ≥5 mm or who report any symptoms consistent with TB disease should undergo further examination and testing for TB 

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Evaluation and Follow-up of Children <5 Years of Age
        - Always assigned a high priority as contacts
        - Should receive full diagnostic medical evaluation, including a chest radiograph
        - If TST ≤5 mm of induration and last exposure <8 weeks, LTBI treatment recommended (after TB disease excluded)
        - Second TST 8–10 weeks after exposure; decision to treat is reconsidered

Negative TST – treatment discontinued

Positive TST – treatment continued

Evaluation and Follow-up of Immunosuppressed Contacts
        - Should receive full diagnostic medical evaluation, including a chest radiograph
        - If TST negative ≥8 weeks after end of exposure, full course of treatment for LTBI recommended (after TB disease is excluded)

Medical Treatment for Contacts with LTBI

Health Department Responsibilities 
        - Focusing resources on contacts in most need of treatment
        - Monitoring treatment, including that of contacts who receive care outside the health department
        - Providing directly observed therapy (DOT), incentives, and enablers 

Window-Period Prophylaxis
        - The frequency, duration, and intensity of exposure
        - Corroborative evidence of transmission from the index patient 

Decision to treat contacts with a negative skin test result should take the following factors into consideration

Prophylactic Treatment
        - With HIV infection
        - Taking immunosuppressive therapy for organ transplant
        - Taking anti-tumor necrosis factor alpha (TNF-α) agents

Prophylactic treatment (after TB disease is excluded) of presumed M. tuberculosis infection recommended for persons 

Treatment After Exposure to Drug-Resistant TB
        - Consultation with physician with MDR expertise recommended for selecting a LTBI regimen
        - Contacts should be monitored for 2 years after exposure

Selecting Contacts for Directly Observed Therapy
        - Contacts aged <5 years
        - Contacts who are HIV infected or otherwise substantially immunocompromised
        - Contacts with a change in their tuberculin skin test status from negative to positive
        - Contacts who might not complete treatment because of social or behavior impediments

When to Expand a Contact Investigation

Determining When to Expand a Contact Investigation

Consideration of the following factors recommended
        - Achievement of program objectives with high- and medium-priority contacts
        - Extent of recent transmission

Unexpectedly large rate of infection or TB disease in high-priority contacts

Evidence of second-generation transmission

TB disease in any contacts who had been assigned low priority

Infection in any contacts aged <5 years

Contacts with change in skin test status from negative to positive

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Strategy for Expanding a Contact Investigation
        - Should be based on the investigation data
        - Results should be reviewed weekly
        - In absence of recent transmission, investigation should not be expanded to lower-priority groups

Communicating Through the News Media

Possible Situations for News Coverage

Certain contact investigations have the potential for sensational news coverage. Examples include

Involving numerous contacts (especially children)

Occurring in public settings

Occurring in workplaces

Associated with TB fatalities

Associated with drug-resistant TB 

Reasons for Participating in News Media Coverage (1)
        - Educates the public regarding the nature of TB
        - Reminds public of continued presence of TB
        - Provides a complementary method to alert exposed contacts of the need for seeking medical evaluation
        - Relieves unfounded public fears regarding TB 

Reasons for Participating in News Media Coverage (2)
        - Illustrates the health department’s leadership in communicable disease control
        - Ensures that constructive public inquiries are directed to the health department
        - Validates the need for public resources to be directed to disease control

Potential Drawbacks to News Coverage
        - Increase public anxiety
        - Cause unexposed person seeking unnecessary medical care
        - Contribute to unfavorable views of the health department
        - Contribute to spread of misinformation
        - Trigger unconstructive public inquiries
        - Unintended disclosure of confidential information

Strategy for News Coverage
        - Anticipatory preparation of clear media messages is recommended
        - Develop communication objectives
        - Issue news release in advance of any other media coverage
        - Collaborate with partners outside of the health department 

Data Management and Evaluation of Contact Investigations

Data Collection
        - Management of care and follow-up index patients and contacts
        - Epidemiologic analysis of investigation in progress and investigations overall
        - Program evaluation using performance indicators that reflect performance objectives 

Three broad purposes in contact investigations

Reasons Contact Investigation Data are Needed
        - Presents broad amount of demographic, epidemiologic, historic, and medical information needed to provide comprehensive care
        - Provides information on process steps necessary for monitoring timeline objectives
        - Provides information needed to reassess investigation strategy

Confidentiality and Consent in Contact Investigations

Safeguarding Confidentiality	
        - Challenging and difficult during contact investigations
        - Essential to maintaining credibility and trust
        - Constant attention required to maintain confidentiality
        - Specific policies for release of confidential information related to contact investigations are recommended 

Confidentiality and Consent
        - Contact investigation policies and training
        - Informed consent
        - Site investigations
        - Other medical conditions besides TB

TB control programs should address the following confidentiality and consent issues before initiation of contact investigations

Staffing and Training for Contact Investigations

Staffing and Training for Contact Investigations
        - Contact investigations involve personnel in the health department and other health care delivery systems
        - Contact investigation tasks require multiple functions and skills
        - Training is essential for successful contact investigations

Contact Investigations in Special Circumstances

Definition of an Outbreak
        - During (and because of) a contact investigation, 2 or more contacts are found to have active TB, regardless of their assigned priority; or
        - Any 2 or more cases occurring within a year of each other, discovered to be linked, and the linkage is established outside of a contact investigation

TB Outbreaks
        - A TB patient was contagious
        - Contacts were exposed for a substantial period of time
        - The interval since exposure has been sufficient for infection to progress to disease (interval may be shortened by HIV infection)

A TB outbreak is a sign of extensive transmission and implies that

Develop Outbreak Strategy Based on Risk Factors
        - Contagious TB undiagnosed or untreated for an extended period, or an extremely contagious case
        - Source patient visiting multiple sites
        - Patient and contacts in close or prolonged company
        - Environment promoting transmission
        - Contacts very susceptible to disease after   M. tuberculosis infection
        - Gaps in contact investigations and follow-up
        - Extra-virulent strain of M.tuberculosis

Congregate Settings
        - Substantial number of contacts
        - Incomplete information regarding contact names and locations
        - Incomplete data for determining priorities
        - Difficulty in maintaining confidentiality
        - Collaboration with officials and administrators who are unfamiliar with TB
        - Legal implications
        - Media coverage

Concerns associated with congregate settings

Congregate Settings – Designating Priorities
        - Site specific
        - Customized algorithm required for each situation

Source-case characteristics

Duration and proximity of exposure

Environmental factors that modify transmission

Susceptibility of contacts

Congregate Settings - Setting-Based Investigation
        - Interview and test contacts on site is optimum approach
        - Alternative is evaluation at the health department with additional personnel and extended hours
        - As last resort, notify contacts in writing to seek diagnostic evaluation with their own health care provider 

Correctional Facilities
        - Establish preexisting formal collaboration between correctional and public health officials
        - Trace high-priority contacts who are transferred, released, or paroled before medical evaluation for TB
        - Low completion rate is anticipated unless follow-through supervision can be arranged for released or paroled inmates

Workplaces
        - Duration and proximity of exposure can be greater than for other settings
        - Details to gather from index patient during initial interview include

Employment hours

Working conditions

Workplace contacts
        - Occasional customers of workplace should be designated as low priority

Hospitals and Other Health-Care Settings
        - Personnel collaborating with hospitals and other health-care agencies should have knowledge of legal requirements
        - Plan investigation jointly with health department and setting (division of responsibilities)
        - Majority of health-care settings have policies for testing employees for M. tuberculosis infection

Schools
        - Early collaboration with school officials and community members is recommended
        - Issues of consent, assent, and disclosure of information more complex for minors
        - Site visits should be conducted to check indoor spaces, observe general conditions, and interview maintenance personnel regarding ventilation

Shelters and Other Settings Providing Services for Homeless Persons
        - Challenges include 

Locating the patient and contacts if mobile

Episodic incarceration

Migration from one jurisdiction to another

Psychiatric illnesses

Preexisting medical conditions
        - Site visits and interviews are crucial
        - Work with setting administrators to offer onsite supervised intermittent treatment

Interjurisdictional Contact Investigations
        - Requires joint strategies for finding contacts, having them evaluated, treating infected contacts, and gathering data
        - Health department that counts index patient is responsible for leading the investigation and notifying health departments in other jurisdictions

Source-Case Investigations

Source-Case Investigations
        - Seeks the source of recent M.tuberculosis infection
        - In the absence of cavitary disease, young children usually do not transmit M.tuberculosis to others
        - Recommended only when TB control program is achieving its objectives when investigating infectious cases

Child with TB Disease
        - Source-case investigations considered for children <5 years of age
        - May be started before diagnosis of TB confirmed

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Child with LTBI
        - Search for source of infection for child is unlikely to be productive
        - Recommended only with infected children <2 years of age, and only if data are monitored to determine the value of the investigation

Procedures for Source-Case Investigation
        - Same procedure as standard contact investigation
        - Patient or guardians best informants (associates)
        - Focus on associates who have symptoms of TB disease
        - Should begin with closest associates

Data collection
        - Number of index patients investigated for their sources
        - Number of associates screened for TB disease
        - Number of times a source is found

Data needed for assessing the productivity of source-case investigations

Cultural Competency and Social Network Analysis

Cultural Competence
        - Knowledge and interpersonal skills that allow health-care providers to appreciate and work with persons from cultures other than their own
        - Ability to understand cultural norms and to bridge gaps requires training and experience

Social Network Analysis
        - Social Network – linkage of persons and places where M. tuberculosis is spread via shared air space
        - Social Network Analysis – methodology of visualizing and quantitating the relative importance of members in a social network  
        - Social Network Analysis assumes there is some detectable patterning of the TB cases and their contacts in a community

Personal Networks for Two TB Cases

Ted

Ali

Moe

Rita

Bill

Juan

Rose

Ted

Combined: A Social Network

Ali

Moe

Rita

Allows review of multiple rather than individual personal networks 

102

Bill

Juan

Rose

Ted

Combined: A Social Network with Place

Ali

Moe

Rita

Mel’s Bar

Bill

Juan

Rose

Ted

Social Network Analysis – Approach (1)
        - Provides a systematic method to deal with data already gathered in routine contact investigations
        - Analysis of the network can help identify important contacts (i.e., those most likely to be infected)
        - Real-time monitoring of network growth may facilitate early detection of outbreaks 

Social Network Analysis – Approach (2)
        - May help programs focus control efforts
        - May offer effective way to list contacts and assign priorities
        - Has been tested retrospectively on TB outbreak and contact investigations

Reference

Guidelines for the Investigation of Contacts of Persons with Infectious Tuberculosis: Recommendations from the National Tuberculosis Controllers Association and CDC. MMWR 2005; 54 (No. RR–15)

 http://www.cdc.gov/mmwr/pdf/rr/rr5415.pdf

Continuing Education Credits (1)
        - Participants will be able to receive one of the following

Continuing Medical Education (CME) credit – 2.75 hours

Continuing Nursing Education (CNE) credit – 3.2 hours

Continuing Education Unit (CEU) – 0.25 hours

Certified Health Education Specialist (CHES) credit – 2.5 hours
        - Participants are required to read and study the guidelines, take a test, and complete an evaluation.

Continuing Education Credits (2)
        - MMWR CE Credit http://www.cdc.gov/mmwr/cme/conted.html
        - Continuing education credits will be available until December 16, 2008

Additional Resources

For additional information on TB, visit the CDC Division of Tuberculosis Elimination Website at http://www.cdc.gov/tb

Guidelines Available Online

CDC’s Morbidity and Mortality Weekly Report - http://www.cdc.gov/mmwr